[Bug tree-optimization/54245] [4.8 regression] incorrect optimisation

[wschmidt at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=54245

--- Comment #4 from William J. Schmidt <wschmidt at gcc dot gnu.org> 2012-08-15 13:27:38 UTC ---
Author: wschmidt
Date: Wed Aug 15 13:27:29 2012
New Revision: 190412

URL: http://gcc.gnu.org/viewcvs?root=gcc&view=rev&rev=190412
Log:
gcc:

2012-08-15  Bill Schmidt  <wschmidt@linux.vnet.ibm.com>

    PR tree-optimization/54245
    * gimple-ssa-strength-reduction.c (legal_cast_p_1): New function.
    (legal_cast_p): Split out logic to legal_cast_p_1.
    (analyze_increments): Avoid introducing multiplies in smaller types.


gcc/testsuite:

2012-08-15  Bill Schmidt  <wschmidt@linux.vnet.ibm.com>

    PR tree-optimization/54245
    * gcc.dg/tree-ssa/pr54245.c: New test.


Added:
    trunk/gcc/testsuite/gcc.dg/tree-ssa/pr54245.c
Modified:
    trunk/gcc/ChangeLog
    trunk/gcc/gimple-ssa-strength-reduction.c
    trunk/gcc/testsuite/ChangeLog